Electric heater



23, 1929' J. A. WILLIAMS ET AL, 1,715,109

ELEC TRIC HEATER Filed July 2-2, 1927 J /Yn A W/ ///'0m 5, 51 2/72 Le Guarn/X,

INVENTORS A ORNEY Patented May 28, 1929.

UNITED STATES JOHN A. WILLIAMS AND EUGENE LE QUORNIK, OF RICHMOND HILL, NEW YORK, AS-

SIGNOB/B TO HAMDEN TOOL & METAL WORKS, INQ, OF HAIMDEN, GONNEUIICUT.

ELECTRIC HEATER.

Application m July 22,

Our invention relates to electric heaters of the class in which part of the heater is immersed in water or other liquid for the purpose of imparting heat to same. It has for its main object to provide a heater which utilizes part of the liquid in which it is immersed as a part of its electric circuit and in which the making and breaking of the circuit is automatically governed by the decrease and increase of the temperature of the liquid so that the liquid may be kept at an even, predetermined temperature.

A further object is to provide a heater very economical in its consumption of current and safe from imparting shocks or burns to the person using 1t. A still further object is to provide a heater of simple, strong construction having no coils or other parts likely to burn out or get out of order, easy to manipulate, and inex ensive to manufacture.

These and ot er objects and advanta es will be clearly understood from the following description and from the accompanying drawing of a preferred embodiment, but it will be readily noted that various modifications may be made without departing from the scope of the invention.

In the drawing,

Fig. 1 is a side elevation of the embodiment of our invention,

Fig. 2 is across-sectional, side elevation taken on line 2-2, Fig. 1,

. Fig. 3 is a fragmentary, cross-sectional view showing certain parts of the heater on a greatly enlarged scale,

Fig. 4 is a cross-sectional, top view taken on line 4-4, Fig. 2, and also drawn to an enlar ed scale, and

,ig. 5 is a cross-sectional, side elevation of an auxiliary part.

Referrin now to Figs. 1 and 2, the heater consists of a tubular handle member 1, counterbored at its upper end to receive a cap 2 and an insulating washer 3, and counterll bored at its lower end to receive a screwthreaded shell 4. A comparatively long tube 5 extends downwardly from the handle member and is provided with a flanged sleeve 6 which is securely attached to the tube but slidably mounted in the shell 4. A smaller tube 7 is placed substantially concentrically inside of the lar er tube 5. This tube, which in this preferre embodiment is shorten than preferred 3O 1927. Serial No. 207,837.

the outer tube, terminates at its lower end in a shouldered and internally threaded plug 8.

A tubular, carbon electrode 9 fits snugly inside the lower end of the outer tube and is provided with a plurality of holes 10 which align with similar holes drilled in the tube. Another tubular, carbon electrode 11 of a smaller diameter is placed concentrically inside the outer carbon electrode so as to form an annular space 12 between them. This construction is plainly shown on the enlarged view Fig. 4.

The extreme lower end of the outer tube is counterbored to receive an insulating washer 13 and a semi-spherical cap 14. A screw 15, passing through the washer 13 and screwed into the plug 8, clamps both the electrodes against a resilient, insulating gasket 16. However, the construction is such that when the Washer 13 is seated in the'counterbore in the outer tubethe inner electrode buts against the end of the plu 8 and makes electric contact therewith. t is evident that when the heater is immersed in liquid, part of this liquid will enter the annular space 12 but is prevented from flowing up between the tubes y the gasket 16.

Referring now more particularly to the enlarged view Fig. 3, a metal washer 17 is riveted on the upper end of the inner tube 7 on top of this metal washer an insulating washer 18, having a large center opening 19, is placed and on to of this washer is placed another metal washer 20. A condenser 21, constructed of alternating layers of copper foil and mica and having an insulating center bushin 22, is separated from the metal washer 20 y another insulating washer 23, while an insulating washer 24 is placed on top of the condenser. A bracket 25, having a downwardly extending contact arm 26, is placed under the metal washer 20. All these parts are held together b a screw 27 and nut 28, as plainly shown. e top copper foil of the condenser 21 is electrically connected by a metal strip 29 to the metal washer 20 on which the bracket 26 is clamped.

The upper end of the outer tube 5, which I buts against an insulatin washer 30 placed under the metal washer 1 is provided with an upwardly extending, circular shell 31 which forms a chamber for all the parts sotion. Afrubber'gasketv46 is placed on the.

, metal strip 35,.contact point 36, contact arm ing a contact point 36 riveted near its upper end, is fastened inside the inner tube by means of the screw 37. The contact point36 normally contacts with the contact arm 26.

Two contact springs 38 and 39are secured to the insulating washer 3 by the eyelets 40 and.

41'and the ends of the electric wires42 and 43, contained in the these eyelets.

and the parts secured thereon are free to slide on the outer tube but that this movement is limited by the washer 30 and the flange on the sleeve 6. A compression spring 45 normally holds the handle member in its upper posiouter tub below the sleeve 6,

The operation ofthe heater will now be explained. The preferred embodiment is constructedfor use with a hot water bag or any other appliance into which the cap 4 may be screwed. When thehandle member is screwed into such an appliance, the spring 45 is compressed and the heater moved slightly upward until the gasket 46 is properly seated and forming a water-tight joint. Thecontact spring 39 is now engaged on the end of the screw 27 and the contact spring'38 against the conical side of the projection 34. A current may now flow through the wire 42, contact spring 38, cover 33, shell 31, outer tube 5, electrode 9, throu h the water or liquid contained in the annu ar space 12, electrode 11, plug 8, inner tube 7, thermostatic 26, screw 27, contact spring 39- and back through the wire 43. I

As the temperature of the, liquid increases the thermostatic metal strip curves until it; breaks the contact between the contact point 36 and the contact arm 26, thus shutting 06 the current until the temperature decreases. So eifeetive have we found this'construetion', that in actual practice we have maintained water at a comparatively'high temperature, overan extended period of time, with less than one degree (Fahrenheit) variation in its temperature and with an actual use of current of less than three minutes per hour. By varying the length or gauge of the thermostatic metal it is possible to raise the temperature of the liquid to any reasonable point and to maintain the temperature at that point.

As no current can flow through the heater c rd 44, are soldered in)" until the spring 45 is compressed and as it is at times desirable to use the heater as a plain immersion heater, the part shown in Fig. 5

sorb the are which might otherwise form when the contact point '36 is removed from the contact arm 26, on alternating current the condenser may be omitted and metal elec-. trodes substituted; in fact, by lengthening the inner tube the two tubesmay beused with- ..out any inserted electrodes; I

,YVhile. we have described andillustrateda heater such'asis'used with a hot water bag p 7. y and on direct current, we do not wish to limit It will be noted that the-handle'me'mber 1 our invention to any particular use, but desire to. employ it within the full scopeof the appended claims.

What we claim as our invent-ion and-desire". i,

to secure by Letters Patent is: 1. In an electric heater ofthe 'clas'sdescribed, a handle member,1a'n-outer-tube'ezi tending from saidhandle member,"-a smaller tube located-concentrically within said'outer tube, a non-metallic electrode inserted in the lower end of said outer tube, another smaller" non-metallic electrode attached to the inner. tube, said electrodes electrically insulated from eachother and provided with means for I connecting them to an electric current, and

a thermal switch located inside the heaterfor making and breaking said current.

2. In an electric heater of the class described, a handle member, an outer tube exelectric current, and a thermal switch located inside the inner tube for'making and breaking said current.

3-. In an electric heater of the class described, a'handle member, an outer tube ex-. tending from said handle'member, a smaller tube located inside said outer tube and spaced therefrom, a non-metallicelectrode inserted in the outer tube, another smaller non-metallic electrode attached to the inner tube, said electrodes electrically connectedvto the respective tubes but electrically insulated from" each other, means for connecting said tubes to an electric current, a thermal switch located inside the inner tube, and a condenser so connected as to absorb the are from said thermal switch.

4. In an electric heater of the class described, a handle member having a screwthreaded portion, an outer tube having a slidable movement in said handle member, a smaller tube located inside said outer tube and spaced therefrom, a non-metallic electrode inserted in the outer tube, another smaller.non-metallic electrode attached to the inner tube, said electrodes electrically connected to the respective tubes but elec 10 trically insulated from each other, means for connecting said tubes to an electric current, a thermal switch located in the inner tube, and an additional switch contained in the handle member and operated by the sliding 5 movement of the outer tube.

5. In an electric heater of the class described, a handle member, an outer tube extending from said handle member and closed atits lower end, a smaller tube located con- 0 centrically within said outer tube, a non-metallic electrode inserted in the lower end of said outer tube, a plurality'of perforations formed in said electrode and aligned with perforations drilled in the outer tube, an-

25 other smaller non-metallic electrode attached to the inner tube, said electrodes electrically insulated from each other and having means for connecting them to an electric current, means for preventing the liquid which en- 30 ters through the perforations when the heater is immersed from flowing between the tubes, and a thermal switch located inside the inner tube.

6. In an electric heater of the class described, a. handle member, a tube extending from said handle, member and provided with perforations at'its free end, a tubular electrode inserted in the end of said tube, perforat-ions formed in said electrode aligning with the perforations in the tube, a smaller electrode inserted concentrically in said tubular electrode and insulated therefrom, a thermal switch located inside the tube, said smaller electrode electrically connected to said switch, means for preventing liquid from entering the tube above the said elec-.

trodes, and means for connecting said tube and said switch to an electric current.

7. In an electric heater of the class described,.a tube, an outer tubular electrode having a plurality of perforations, an inner tubular electrode, a shouldered bushing having a threaded hole, a resilient insulating packing placed on said bushing, an insulatin washer, said electrodes placed inside of said tube their endsabutting against said packing and said washer, and a screw for securing all of said parts in their correct positions within said tube.

JOHN A. WILLIAMS. EUGENE LE QUORNIK. 

